Size yourself up

When you look at yourself, your brain uses a different neural pathway to when you're looking at someone else. Coupled with the pressures of modern society, this can lead to negative body perceptions, mental health issues and eating disorders.

Scientists from the EU-funded SIZE MATTERS (Size matters: Investigating the link between affective and perceptual body representations using multisensory illusions and brain imaging) project used magnetic resonance imaging (MRI) and virtual reality to explore the neural link between body perception and body satisfaction.

SIZE MATTERS used virtual reality headsets to induce full-body illusions by showing participants a mannequin or another person’s body from a first-person point of view. Synchronised touches on the body of the participant and the body shown on the headset helped the illusion of ownership over the displayed body. Displayed bodies were either slim or obese.

As a control condition, participants also experienced asynchronous touches to eliminate the illusion of ownership. Functional MRI was then used to identify neural links between body perception and body satisfaction.

Over all, people were more satisfied with thinner bodies and less satisfied with obese bodies. The researchers also found that there is a direct neural link between body satisfaction brain regions and body perception brain regions.

Females, and people with higher eating disorder traits, had stronger emotional responses to illusionary changes in body size and displayed different responses in the brain. These different brain responses implicate areas in the brain previously associated with anorexia nervosa to eating disorder vulnerability in healthy people.

The results of this study contribute to our understanding of body self-image and eating disorders. The data from this study will be useful to develop prevention and treatment strategies for eating disorders.